Nizwa University

College of Pharmacy and Nursing

Practical Notes

Pharmaceutics I

PHCY 100

Under supervision of Dr. Anil Philip


Learning Outcome

·  The students shall be able to:

·  Prepare solutions namely:

i. simple solutions

ii. aromatic waters

iii. mouthwashes

iv. gargles

v. elixirs

·  Perform calculations in pharmacy concerning:

i. expression of concentration

ii. quantities from a master formula

iii. quantity of ingredients too small to

weigh or measure accurately

iv.changing concentrations to small quantities

• Make extemporaneous labels

Pharmaceutical Formulation and Dispensing

DRUG DOSAGE

The administration of drugs is one of the most important duties performed in caring for sick and injured patients.

The appropriate drug given in the correct dosage will very often hasten a patient's recovery. On the other hand, an inappropriate drug or dosage may worsen a patient's condition or even result in his death

Extemporaneous preparations: The making of the medicine for particular individuals from an appropriate formula from its raw materials. They are preparations made in small quantities for a short period of time.

Prescription interpretation

What is prescription?

Prescription is an order for medication issued physician, or dentist, or other licensed practitioner.

Prescriptions designate to specific medication and dosage to be prepared by pharmacist and administered to the patients.

What is the role of pharmacist regarding prescription?

The pharmacist should translate the order written by the physician into accurate medication that allows the patient to understand and follow.

The pharmacist must be familiar with the following parts of prescription and the prescription abbreviations.

Parts of prescription:

1-Patient information: - include the name and address of the patient

2- Date: - The date the prescription was written, that may differ from the data of filling.

3-Superscription: - The Rx symbol: which is contraction of the Latin word; = recipe = you take

This recipe: - means that pharmacist is receiving this prescription from the physician to be prepared by the pharmacist

4- Inscription : " Formula" Is the part that include the prescribed mediation;

- the name

-- quantities ( you should note that " g means a solid "

"ml means a liquid "

-- prescribed ingredients

5-Subscription: - is the part include the dispensing direction (commonly used in abbreviation) + Dose

Eg: Dis ----- Dispense

Div ----- divide

M ---- Mix

Ft --- make

Dose is the quantity needed for a particular patient

6-Signature " Sig" of Signa : - is the dose regimen or

"the directions to the patients"

Dose regimen means

a) one tablets , one teaspoonful, one ampoule

b) frequency as 3 times every days, every 6 hours, every month

c) Duration : for 3 days, for one month, for one year

7-Special instructions : - This part used to indicate the number of authorized refills

Example

Name : Ahmed mohammed Date : 8/10/2009

Address : 123 main street, Town, Country

Rx

Atropine sulfate 10 mg

Diphenoxylate HCl 160 mg

M div caps # 20

Sig : I bid prn diarrhea

Refills 1

M div caps # 20 = mix and divide the medication in the inscription into 20 capsules

I bid prn diarrhea = the direction call for the patient to take one capsule two times a day as needed for diarrhea

Table 1.1.Common Latin names and abbreviations

TERM OR PHRASE / ABBREVIATION / MEANING
Ad / to, up to
ad libitum / ad lib / freely, at pleasure
ana / āā / of each
ante / a / before
ante cibum / a.c. / before meals
bene / ben / well, good
bis / twice
bis in die / b.i.d. / twice a day
capiat / Cap / let the client take
capsula / caps. / capsule
cum / c / with
dentur tales doses / D.T.D., d.t.d. / give of such doses
dispensa / Disp / dispense
et / and
ex modo praescripto / e.m.p / after the manner prescribed (as directed)
fac, fiat, fiant / ft. / make, let it be made
granum / gr. / grain
gutta, guttae / gt., gtt. / Drop, drops
hora / hor., h. / hour
hora somni / hor. som., h.s. / at the hour of sleep
injection / inj / injection
inter / between
lotio / lot. / lotion
non repetatur / non rep., non repetat / do not repeat
octarius / O. / pint
oculus dexter / O.D. / right eye
oculus sinister / o.s., O.S / left eye
oculi unitas / O.U. / both eyes
omni hora / Omn. hor. / every hour
per / through, by means of
per os / P.O. / by mouth
placebo / I will satisfy
post cibum / post cib., p.c. / after meals
pro re nata / p.r.n. / as needed, as circumstances require
pulvis / pulv. / powder
quantum satis / q.s. / a sufficient quantity
quantum satis ad / q.s. ad / a sufficient quantity to make
quaque / q. / every
quaque die / q.d / every day
quaque hora / q.h. / every hour
quater in die / q.i.d. / four times a day
recipe / Rx / take thou
semi, semis / ss / a half
signa / sig. / write, label
sine / s / without
solve, solvere, solutus / solv. / dissolve
statim / stat / immediately
tabella / tab. / tablet
ter / t. / three
ter in die / t.i.d., tid / three times daily
unguentum / ung. / an ointment
ut dictum / Ut dict. / as directed

Table 1.2. Time of administration.

ABBREVIATION / MEANING
a.c. / before meals
q.h. / every hour
b.i.d., bid / twice a day
q.i.d., qid / four times a day
h.s. / at bedtime
q.3h., q3h / every 3 hours
non rep / do not repeat
q.6h., q6h / every 6 hours
p.c. / after meals
stat. / Immediately
p.r.n. / as needed
t.i.d., tid / three times a day

Table 1.3. Routes of administration and dosage forms.

ABBREVIATION / MEANING
I.M., IM / intramuscularly
s.c., s.q. / subcutaneously
I.V., IV / intravenously
P.O. / by mouth
O.D. / right eye
caps. / capsule
o.s., O.S. / left eye
liq. / liquid, solution
O.U. / both eyes
tab. / tablet
p.r.n. / as needed
t.i.d., tid / three times a day

Table 1.4. Metric system abbreviations.

WEIGHT / abbreviations / VOLUME / abbreviations
milligram / mg. / milliliter / ml.
gram / g., Gm. / cubic centimeter / cc.
kilogram / kg., Kg. / liter / l., L.

Table 1.5. Apothecary system abbreviations.

WEIGHT / abbreviations / VOLUME / abbreviations
grain / gr. / fluid drachm
drachm / fluid ounce / fl. oz.,
ounce / oz., / pint / O., pt.
quart / qt.
gallon / C., gal.

NOTE:

The fluid dram and the fluid ounce are often abbreviated without the “f” being

used.

It can be assumed that when the dram symbol is used with a liquid, the

fluid dram is intended.

Labeling

Labels are very important aspect of pharmaceutical products. They are supposed to guide everyone concerned. The labels are going to be issuing guidelines to pharmacists, doctors, nurses, and patients. There are very serious issues that may arise out of inadequate information or improper information. Drug information is vital as drug itself, which leads to safe and effective handling and usage of medications.

Label refers to :

-  the type of dispensed product

-  Dose

-  Route of administration

-  Special instruction : e.g

"Shake the Bottle" especially for suspension and emulsion

"Keep in a cool place" for storage condition

Label color

White for internal use

Equipment

The student should be able to select the correct equipment or tools for compounding the prescription such as:

1-  Balance :- for weighing

2-  Measuring cylinder : for measuring the liquid ( you should notice that the level of liquid is read to the bottom of the meniscus and the measure is vertical)

Mix and grinding : Mortar and pestle

A- Porcelain mortar

B- Glass mortar

ِ5- Heating source:

Water-bath

Liquid dosage may be in form of:

1- Solutions

2- Suspensions

3- Emulsions

1-  Solutions are homogenous liquid preparations that contain two or more water soluble components.

The water soluble components (drug) are termed solutes that dissolve in a solvent (vehicle).

Solute is the component that dispersed as small molecules or ions in the solvent.

Vehicle is defined as the liquid or solvent in which the medically active ingredients are dissolved or suspended. It is usually present in greater amount than solute.

Vehicle used may be:

Inert e.g water

Flavored e.g. peppermint water

Persevered and sweetened e.g. chloroform water

Have a medicinal property e.g. Senna infusion.

The only exception for the solution is the syrup that contains 66.7 w/w solute and 33.3 w/w solvent.

General Methods for Preparation of Solutions.

1- Dissolve the solids in about 3/4 of the vehicle (solvent)

2- Examine the solution by holding it against the light, if it not clear, filter through a filter paper placed in a funnel, then rinse with aqueous vehicle.

3- Add any liquid ingredients after measuring each and rinse the vessel used with a little of the aqueous vehicle.

4- In the case of liquid contains volatile substance adjust the mixture to volume minus the volume of volatile liquid, transfer to the bottle , then add the measured volume of the volatile liquid and cork immediately.

5- Adjust the final volume of the preparation using graduated measuring cup with the remaining amount of the vehicle.

6- Transfer the mixture to the bottle, and then polish to remove finger-mark and then attach the written label.

The reason for using 3/4 of the vehicle in preparing liquid preparations is:

1- The volume occupied by the other ingredients will rarely exceed the remaining 1/4; but if it will exceed, the quantity of the vehicle must be reduced.

2- Dissolving solid substances should be done by using as much solvent as convenient.

A)  Solution by chemical reaction: - results from the reaction between two or more solutes with each other in a suitable solvent.

B)  Solution by extraction: solution of active ingredient from natural sources (vegetable or animal origin) , that extracted with water or water-organic solvent mixture , or organic solvent

Experimental Work

Solutions prepared by simple method

1- Rehydran solution

/ Given amounts / Calculated amounts
Potassium Citrate / 0.05 g
Sodium Chloride / 0.05 g
Sodium Bicarbonate / 0.045 g
Dextrose / 0.01 g
Chloroform water to / 1.00 ml

Calculations

Corr. Factor= Desired * Quantity

Have

Use: Dehydration caused by diarrhea is one of the biggest single killers of children in the modern world and diarrhea itself is one of the major causes of nutritional loss and poor growth (due to loss of electrolytes, water and nutrition from the body)

Rehydran solution is used to replace the liquid being lost.

Label

2- Iron ammonium Citrate Mixture

Given amounts / Calculated amounts
Iron ammonium Citrate / 5 g
Tincture of Nux Vomica / 3 ml
Syrup / 10 ml
Purified water to / 90 ml

Use

For treatment of anemia

Label

3- The Cough Syrup

Given amounts / Calculated amounts
Ammonium Chloride / 5 g
Liquid extract of Liquorice / 5 ml
Syrup / 2. 5 ml
Purified water to / 50 ml

Use: For treatment of reproductive cough

Label

Intermediate preparations

There are many pharmaceutical solutions which are designed for use during the manufacturer of other preparations and which are rarely administered by themselves, for example, aromatic waters, infusions, extracts, spirits, and syrups.

1- Aromatic Waters

Aromatic water is also known as medicated waters. They are clear, saturated aqueous solution or volatile oils or other aromatic or volatile substances. The preparations should be free from other foreign odors. Their odor or tastes are usually similar to those of the drug or volatile substances from which they are prepared. They are used principally as flavored or perfumed vehicle.

.

1- Peppermint water

Oil of menthe / 0.2 ml
Talc / 1.5 g
Water to / 100 ml

Use: Carminative and flavored vehicle

Label

2- Camphor water

Camphor is soluble only 1 in 700 of water, and the strength of camphor water is 1 in 1000 that is near to saturation.

Camphor is very soluble in alcohol. The water is prepared by dissolving the camphor in alcohol adding this solution in small portions to the water, each addition being followed by vigorous shaking. The addition of the alcoholic solution to water yield a finely-divided precipitate of camphor, which in this condition, pass into solution more quickly than camphor simply powdered in a mortar. The alcohol may then be considered as a distributing agent.

Camphor / 1 g
Alcohol / 15 ml
Purified Water to / 100 ml

Uses

Can be used for

Carminative internally and

antiseptic and anesthetic in eye lotions.

Label

Syrups

Syrups are concentrated solutions of sugar such as sucrose in water or other aqueous liquid.

·  When purified water is used alone in preparing the solution of sucrose, the preparation is known as simple syrup.

·  When the aqueous preparation contains some added medicinal substance, the syrup is called medicated syrup.

·  When the aqueous preparation contains various aromatic or pleasantly flavored substances, the syrup is called flavored syrup and used mainly as a vehicle or a flavor in prescriptions.

The concentration of sucrose in the syrup must be 66.7% w/w (E.P) or 85 % W/V (USP) to approach but not reach saturation.

This is because:

·  Less than this concentration will make the solution susceptible to mold growth.